Hammond Power Solutions Inc.
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BUCK-BOOST TRANSFORMERS
Buck-boost transformers represent an economical way to both raise supply voltage caused by line drop or
equipment demand on the distribution system; or lower voltage caused by increased system voltages due
to supply line adjustments. Some loads including lighting and resistive loads, require a stable supply to
maintain performance. The detrimental effects of incorrect supply line voltage can cause equipment
failure.
Key Features:
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Ratings from 50VA to 5000VA
Primary Voltage 120/240, 240/480
50/60 Hz frequency
Single & three phase
UL listed
CSA certified
10 year warranty
For more information, click one of the links below:
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Buck-Boost Catalog Section (HTP-08 Catalog Sec. 2)
Enclosure Drawings, Electrical Connection Diagrams, Termination Details (HTP-08 Catalog Sec. General Info)
Buck-Boost Installation Manual (IOMGE Installation Manual)
©2008 Hammond Power Solutions Inc. All Rights Reserved
HPS UniversalTM
BUCK-BOOST TRANSFORMERS
SECTION 2
Why Use Buck-Boost Transformers?
SECTION 2
The advantages of using a buck-boost transformer over an equivalent standard isolation transformer are as
follows:
Advantages
1) Used in a variety of applications
2) Inexpensive
3) Smaller and lighter
4) More efficient 5) 5-10 times increase in kVA
Disadvantages
1) No circuit isolation
2) Cannot create a neutral
3) KVA and voltages do not match what’s
on the nameplate kVA and voltages.
Buck-Boost Application
Buck-boost transformers offer an economical solution to the adjustment of line voltages that are slightly
above or below normal. When a buck-boost transformer is connected as an autotransformer, only a portion of the
load kVA is actually transformed. The majority of the load kVA is passed directly through to the source. For this
reason a buck-boost transformer may be used to supply a much larger load kVA than is indicated on the nameplate.
Buck-boost transformers can be used to adjust stable voltages only. Fluctuating line voltages should be
regulated with a Line Voltage Conditioner. Refer to ‘Section 6’ for details.
BUCK-BOOST STANDARD SPECIFICATIONS
50 to 1000 VA
1500 to 5000 VA
UL Listed
File: E50394
File: E50394
CSA Certified
File: LR3902
File: LR3902
Frequency
50/60 Hz
50/60 Hz
Insulation System
130°C (80°C rise)
180°C (115°C rise)
Standard Design
Single Phase, welded core construction
made with high quality, high permeability
silicon steel laminations. Computer
designed coils, accurately wound from
high quality magnetic wire.
Single Phase, welded core construction
made with high quality, high permeability
silicon steel laminations. Computer
designed coils, accurately wound from
high quality copper magnetic wire.
Encapsulation
All units from 50VA to 5kVA are
encapsulated with electrical grade silica
sand and resin compounds.
All units from 50VA to 5kVA are
encapsulated with electrical grade silica
sand and resin compounds.
Enclosure Type
Heavy Duty Encapsulated NEMA Type 3R
Heavy Duty Encapsulated NEMA Type 3R
(optional NEMA 4, 4X and 12 available)
(optional NEMA 4, 4X and 12 available)
Enclosure Finish
ANSI 61 Grey, UL50
ANSI 61 Grey, UL50
Termination
Front accessible separate high and
low voltage lead wires or copper tabs.
Front accessible separate high and
low voltage lead wires or copper tabs.
Conduit Knock-Outs
Side and rear standard on all units.
Side and rear standard on all units.
Mounting
Standard Wall Mounting.
Standard Wall Mounting.
© Hammond Power Solutions Inc.
70
Data subject to change without notice.
HPS UniversalTM
BUCK-BOOST TRANSFORMERS
SECTION 2
Single Phase Specification Tables
Group A
Primary
Voltage
120/240
Secondary
12/24
Voltage
SECTION 2
50/60 Hertz
VA
Catalog
Number
Case
Style
(Page 249)
50
100
150
200
250
350
500
750
1000
1500
2000
3000
5000
QC05ERCB
QC10ERCB
QC15ERCB
QC20ERCB
QC25ERCB
QC35ERCB
QC50ERCB
QC75ERCB
Q1C0ERCB
Q1C5ERCF
Q002ERCF
Q003ERCF
Q005ERCF
Approx. Dimensions
(Inches)
Width
Depth
Height
NQ0
NQ0
NQ0
NQ1
NQ1
NQ1
NQ2
NQ2
NQ3
NQ4
NQ4
NQ5
NQ5
3.75
3.75
3.75
4.50
4.50
4.50
5.00
5.00
5.88
7.00
7.00
10.00
10.00
5.25
5.25
5.25
5.75
5.75
5.75
4.75
4.75
5.50
6.50
6.50
7.75
7.75
7.25
7.25
7.25
7.25
7.25
7.25
9.25
9.25
10.00
11.25
11.25
17.25
17.25
Case
Style
Approx. Dimensions
(Inches)
Width
Depth
Height
Approx.
Weight
(Lbs.)
Mtg Type
6
7
8
11
13
14
15
18
25
36
46
65
105
W
W
W
W
W
W
W
W
W
W
W
W
W
Approx.
Weight
(Lbs.)
Mtg Type
6
7
8
11
13
14
15
18
25
36
46
65
105
W
W
W
W
W
W
W
W
W
W
W
W
W
W - Wall
Group B
Primary
Voltage
120/240
Secondary
16/32
Voltage
50/60 Hertz
VA
Catalog
Number
(Page 249)
50
100
150
200
250
350
500
750
1000
1500
2000
3000
5000
QC05ESCB
QC10ESCB
QC15ESCB
QC20ESCB
QC25ESCB
QC35ESCB
QC50ESCB
QC75ESCB
Q1C0ESCB
Q1C5ESCF
Q002ESCF
Q003ESCF
Q005ESCF
NQ0
NQ0
NQ0
NQ1
NQ1
NQ1
NQ2
NQ2
NQ3
NQ4
NQ4
NQ5
NQ5
© Hammond Power Solutions Inc.
3.75
3.75
3.75
4.50
4.50
4.50
5.00
5.00
5.88
7.00
7.00
10.00
10.00
5.25
5.25
5.25
5.75
5.75
5.75
4.75
4.75
5.50
6.50
6.50
7.75
7.75
78
7.25
7.25
7.25
7.25
7.25
7.25
9.25
9.25
10.00
11.25
11.25
17.25
17.25
W - Wall
HPS UniversalTM
BUCK-BOOST TRANSFORMERS
SECTION 2
Single Phase Specification Tables
Group C
Primary
Voltage
240/480
Secondary
24/48
Voltage
50/60 Hertz
Catalog
Number
Case
Style
(Page 249)
50
100
150
200
250
350
500
750
1000
1500
2000
3000
5000
QC05DTCB
QC10DTCB
QC15DTCB
QC20DTCB
QC25DTCB
QC35DTCB
QC50DTCB
QC75DTCB
Q1C0DTCB
Q1C5DTCF
Q002DTCF
Q003DTCF
Q005DTCF
NQ0
NQ0
NQ0
NQ1
NQ1
NQ1
NQ2
NQ2
NQ3
NQ4
NQ4
NQ5
NQ5
Approx. Dimensions
(Inches)
Width
Depth
Height
3.75
3.75
3.75
4.50
4.50
4.50
5.00
5.00
5.88
7.00
7.00
10.00
10.00
5.25
5.25
5.25
5.75
5.75
5.75
4.75
4.75
5.50
6.50
6.50
7.75
7.75
7.25
7.25
7.25
7.25
7.25
7.25
9.25
9.25
10.00
11.25
11.25
17.25
17.25
Approx.
Weight
(Lbs.)
Mtg Type
6
7
8
11
13
14
15
18
25
36
46
65
105
W
W
W
W
W
W
W
W
W
W
W
W
W
Approx.
Weight
(Lbs.)
Mtg Type
6
7
8
11
13
14
15
18
25
36
46
65
105
W
W
W
W
W
W
W
W
W
W
W
W
W
W - Wall
Three Phase Specification Tables
Group A
Primary
Voltage
120/240
Secondary
12/24
Voltage
50/60 Hertz
VA
Catalog
Number
50
100
150
200
250
350
500
750
1000
1500
2000
3000
5000
QC05ERCB
QC10ERCB
QC15ERCB
QC20ERCB
QC25ERCB
QC35ERCB
QC50ERCB
QC75ERCB
Q1C0ERCB
Q1C5ERCF
Q002ERCF
Q003ERCF
Q005ERCF
Case
Style
(Page 249)
NQ0
NQ0
NQ0
NQ1
NQ1
NQ1
NQ2
NQ2
NQ3
NQ4
NQ4
NQ5
NQ5
© Hammond Power Solutions Inc.
Approx. Dimensions
(Inches)
Width
Depth
Height
3.75
3.75
3.75
4.50
4.50
4.50
5.00
5.00
5.88
7.00
7.00
10.00
10.00
5.25
5.25
5.25
5.75
5.75
5.75
4.75
4.75
5.50
6.50
6.50
7.75
7.75
79
7.25
7.25
7.25
7.25
7.25
7.25
9.25
9.25
10.00
11.25
11.25
17.25
17.25
W - Wall
SECTION 2
VA
HPS UniversalTM
BUCK-BOOST TRANSFORMERS
SECTION 2
Single Phase Connection Diagrams
Low
Voltage
Low
Voltage
Low
Voltage
© Hammond Power Solutions Inc.
X1
H2
X3
H3
X2
H1
X4
H4
X1
H2
X3
H3
X2
H1
X4
H4
X1
H2
X3
H3
X2
H1
X4
H4
X1
H2
X3
H3
X2
H1
X4
81
Connection
Diagram #1
High
Voltage
Connection
Diagram #2
High
Voltage
Connection
Diagram #3
High
Voltage
Connection
Diagram #4
High
Voltage
Data subject to change without notice.
SECTION 2
Low
Voltage
H4
HPS UniversalTM
BUCK-BOOST TRANSFORMERS
SECTION 2
Three Phase Connection Diagrams
Connection
Diagram #5
1
Low Voltage
3 Phase
2
3
2
3
H4 H4
3
Connection
Diagram #7
1
Low Voltage
3 Phase
er
#1
1
2
3
2
3
H4 H4
2
#1
er
rm
X4
X2
X3
Transformer
#3
H4
H2
H3
Transformer
#3
X2
sfo
r
#1 mer
1
High Voltage
3 Phase
2
3
82
H1
H3
H2
H4
X1
X3
X2
X4
H3
Tra
n
r
X3
X1
H4
H2
X1
X4
X4
3
X2
X3
X1
X2
X3
2
e
orm
nsf
Tra #2
© Hammond Power Solutions Inc.
Connection
Diagram #12
1
X4
H4
H2
H3
H3
H2
H4
X1
X3
X2
X4
H1
3
Low Voltage
3 Phase
3
1
sfo
X4
Transformer
#3
Transformer
#3
Connection
Diagram #11
1
er
orm
nsf
Tra #2
H3
H2
H4
X1
X3
X2
X4
2
X1
H4
H2
X1
H4
H2
H3
X3
X2
X3
1
H1
X2
X3
X1
H4
H2
H3
sfo
r
#1 mer
3
for
#1 mer
X4
X4
X2
X4
X3
X1
Tra
n
High Voltage
3 Phase
Tra
ns
3
er
2
Low Voltage
3 Phase
2
orm
nsf
Tra #2
H3
H2
H4
X1
X3
X2
X4
Connection
Diagram #10
1
Low Voltage
3 Phase
X2
1
High Voltage
3 Phase
H1
H4
H2
H3
sfo
r
#1 mer
X1
3
H3
3
1
2
X1
H4
H2
H3
2
Tra
n
Tra
n
#1
er
rm
sfo
Tra
n
Connection
Diagram #9
1
#2
2
X2
X3
er
High Voltage
3 Phase
3
Low Voltage
3 Phase
High Voltage
3 Phase
X1
X1
X4
rm
X3
H3
H1
sfo
1
X2
X3
H2
n
Tra
X4
#2
High Voltage
3 Phase
X4
X2
er
X1
H3
H1
H3
H1
rm
X3
H2
sfo
X4
X2
Connection
Diagram #8
1
Low Voltage
3 Phase
H2
n
Tra
H3
H1
X1
3
H4 H4
H2
X2
X3
2
High Voltage
3 Phase
2
High Voltage
3 Phase
X4
Tra
ns
for
m
sfo
rm
er
Tra
n
X1
X1
#2
SECTION 2
X4
X2
X3
X3
er
1
H2
H3
H1
2
r#
me
for
ns
Tra
rm
X1
X4
X2
sfo
X3
H2
H3
H1
H2
H3
H1
n
Tra
X4
X2
#1
H4 H4
H2
H3
H1
Connection
Diagram #6
1
Low Voltage
3 Phase
er
orm
nsf
Tra #2
2
3
Data subject to change without notice.